An ethnopharmacological survey showed that home remedies prepared with flowers, fruits and roots of Psychotria colorata (Willd. ex R. & S.) Muell. Arg. (RUBIACEAE) are used by Amazonian caboclos as pain killers. These data led to the evaluation of analgesic activity of extracts of P. colorata, using the formalin, writhing and tail-flick methods. This paper reports the Naloxone reversible opioid-like analgesic activity of alkaloids present in leafs and flowers of P. colorata.